Publication Date: 2008 Sep 4 PMID: 18769436Authors: Hanson, J. A. - Chang, C. B. - Graves, S. M. -
Li, Z. - Mason, T. G. - Deming, T. J.Journal: NatureWater-in-oil-in-water emulsions are examples of
double emulsions, in which dispersions of small water droplets within larger oil droplets are
themselves dispersed in a continuous aqueous phase. Emulsions occur in many forms of processing and
are used extensively by the foods, cosmetics and coatings industries. Because of their
compartmentalized internal structure, double emulsions can provide advantages over simple
oil-in-water emulsions for encapsulation, such as the ability to carry both polar and non-polar
cargos, and improved control over release of therapeutic molecules. The preparation of double
emulsions typically requires mixtures of surfactants for stability; the formation of double
nanoemulsions, where both inner and outer droplets are under 100 nm, has not yet been achieved.
Here we show that water-in-oil-in-water double emulsions can be prepared in a simple process and
stabilized over many months using single-component, synthetic amphiphilic diblock copolypeptide
surfactants. These surfactants even stabilize droplets subjected to extreme flow, leading to
direct, mass production of robust double nanoemulsions that are amenable to nanostructured
encapsulation applications in foods, cosmetics and drug delivery.post to:
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